Gallery Quantum interference patterns of electrons on Ag(111) at 5 K Array of magnetic dots each containing 25 Fe atoms Identifying the origin of dentritic growth Quantum interference in triangular pit on Cu(111) Long range interactions between adsorbates: Cu/Cu(111) at 13.5 K (640 kB movie) Long range interactions between adsorbates: Cu/Cu(111) at 15.6 K (1 MB movie) Long range interactions between adsorbates: Co/Cu(111) at 10.2 K (1.9 MB movie) Long range interactions between adsorbates: Co/Ag(111) at 18.5 K (470 kB movie)